Fast and Low-Cost Synthesis of MoS 2 Nanostructures on Paper Substrates for Near-Infrared Photodetectors.

Featured Application: This work presents an analysis of time and temperature influence of microwave-assisted hydrothermal synthesis on the direct growth of 2D-MoS2 nanostructures on cellulose paper substrates, and the production of MoS2-based low-cost photosensors with high responsivity and detectivity values. Recent advances in the production and development of two-dimensional transition metal dichalcogenides (2D TMDs) allow applications of these materials, with a structure similar to that of graphene, in a series of devices as promising technologies for optoelectronic applications. In this work, molybdenum disulfide (MoS₂) nanostructures were grown directly on paper substrates through a microwave-assisted hydrothermal synthesis. The synthesized samples were subjected to morphological, structural, and optical analysis, using techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman. The variation of synthesis parameters, as temperature and synthesis time, allowed the manipulation of these nanostructures during the growth process, with alteration of the metallic (1T) and semiconductor (2H) phases. By using this synthesis method, two-dimensional MoS₂ nanostructures were directly grown on paper substrates. The MoS₂ nanostructures were used as the active layer, to produce low-cost near-infrared photodetectors. The set of results indicates that the interdigital MoS₂ photodetector with the best characteristics (responsivity of 290 mA/W, detectivity of 1.8 × 10⁹ Jones and external quantum efficiency of 37%) was obtained using photoactive MoS2 nanosheets synthesized at 200 °C for 120 min. [ABSTRACT FROM AUTHOR]